BBQ styles tend to get people picking sides because they vary so widely and often have something to then that is unfamiliar to people who are used to another style.

All involve slow cooking. Some are dry, as in dry spices and seasonings are applied but no moisture. Others are wet and are frequently slathered in sauce while cooking. Some have a very strong smokey flavor and some have a strong vinegar taste.

I like most types, except the ones with the strong vinegar flavor. While I won't tell someone they are wrong for liking that, if I accidently bite into the vinegar based BBQ it makes me angry and people being confrontational about it makes a bit more sense.

There is also some pizza rivalries and people who like Chicago deep dish are wrong.